Process of forming vessels from sheet metal.



No. 758,503. PATENTED APR. 26, 1904. H. GPBLEVINS & J. E. WHITTAKER.

PROCESS OF FORMING VESSELS FROM SHEET METAL.

' APPLICATION FILED JULY 1, 1903.

no menu. 2 sums-51mm: 1.

No. 758,503. PATBNTED APR. 26, 1904. H., G. BLEVINS & J. E. WHITTAKER.

PROCESS OF FORMING VESSELS FROM SHEET METAL.

APPLICATION FILED JULY 1, 1903. no 10mm. 7 2 snnn'rs-snnm z- I mil-l Sim 26 Willi Qllllll UN rrnn STATES Patented April 26, 1904.

ATENT rricn.

. HERMANN Gr. BLEVINS AND JAMES E. VVHITTAKER, OF NEWCASTLE,

PENNSYLVANIA.

PROCESS OF FORMING VESSELS FROIVI SHEET METAL.

SPECIFICATION formingpart of Letters Patent No. 758,503, dated. April 26, 1904.

Application filed July 1, 1908. Serial Nol63,8'78. (No specimens.)

To (all whom it may concern:

Be it known that we, HERMANN G. BLEVINS, a citizen of the United States, and JAMES E. IVHITTAKER, a subject of the King of England, residing at Newcastle, in the county of Lawrence and State of Pennsylvania, have invented certain new and useful Improvements in Processes of Forming Vessels from Sheet Metal, of which the following is a specification, reference being had therein to the accompanyingdrawings.

This invention relates to certain new and useful improvements in the process for forming vessels from sheet metal, and is particularly adapted to the forming of teapots, coffeepots, saucepans, and kitchen hardware.

The object of this invention is'to provide a, process whereby a sheet-metal vessel may be cheaply formed without seams or soldered joints.

Our improved process consists of electrically welding the different parts together, thereby doing away with the seams and at the same time providing greater density of the metal at any part where a joint has been formed.

In our improved process the sheet-metal ware is cut into suitable shapes, and after being bent into the desired form the two parts forming the joint are overlapped, contact between the said two parts being mechanically secured. The two terminals of a suitable source of electrical energy are applied thereto adjacent to said joint and the electrical current allowed to pass therethrough until a suitable welding heat of the parts has been reached, and then by means of a suitable press or hammer the parts are forced together, thereby securing a permanently-welded joint.

One difliculty which has been apparent in all previous attempts to weld sheet metal has been that as the sheet metal becomes heated the electrical resistance thereof increases, thereby cutting down the strength of the current. In carrying out our invention we provide in the electrical circuit a regulator, whereby the initial current is caused to pass through a series of resistances; but when the current is decreased, caused by the heating of the parts to bewelded, the said resistances are automatically cut out step by step, thus maintaining a current of constant amperage or quantity.

For more detail description of this invention reference will be had to the accompanying drawings, in which Figure l is a perspective view of one form of press which may be adapted for use in carrying out our improved process. Fig. 2 is a diagrammatical view illustrating the electrical circuit as used in our process, the same, as shown, being applied to the welding of a cylinder. Fig. 3 is a sectional elevation showing a closure being applied to one end of a cylinder. Fig. 1 illustrates an out-let being applied to.one side of a cylinder. Fig. 5 illustrates a blank from which the cylinder may be formed. Fig. 6 is an end view of the cylinder suitably flanged to have a closure formed thereon. Fig. 7 is a blank which may form the closure on the cylinder. Fig- 8 is a sectional view of the cylinder after the closure has been formed on one end thereof. Fig. 9 is a sectional elevation of the outlet, which may be welded to one side of the cylinder. Fig. 10 is a sectional view of the cylinder having the outlet welded on one side thereof. Fig. 11 is a perspective view of the same.

In carrying out our improved process a source of power 1, which, as shown in Fig. 2, is a dynamo, (but it may be any other suitable source,) one terminal 2 of which connects with one end of the resistance-coil 3, and the other terminal 4: of said source of power leads to the binding-post 5, which is attached to one portion of the piece of work 6 which is to be welded. A resistance-coil 3 is pro-' vided and a suitable brush 7 attached to the disk or plate 8, the periphery of said plate being suitably formed with teeth, which are adapted to be engaged by the pawl 9, carried by the lever 10, journaled at the axis of said plate. The other end of said lever 10 is attached by a link connection to the core 11 of the solenoid 12, said solenoid having a connection 14: with the brush 7 of the rheostat and the other terminal 15 being connected to the binding-post 16, which is attached to the other end of the piece of.work from that to which the post 5 is attached. A clamp 17 securely holds the two ends of the piece of work to be welded in position, said clamp resting on the insulated pins 18, which are slidably mounted in a support 19, provided on the support 20. A spring 21 normally holds the insulated pin 18 in its upward position; but when the press-head, carrying with it the block 21, is moved downward the said pins 18 are depressed, thereby permitting the work-holder 17 to rest securely against the support 19, and the block 21, pressing on the upper part of said work-holder, will force the metal which has been heated by the electrical current together, thereby welding the same.

The operation of the solenoid 12. which forms the means of regulating the amount of resistance which is in said circuit, is as follows: As the metal to be welded becomes heated the resistance in the same becomes greater, thereby reducing the strength of the current. Thus the electrical attraction of the solenoid 12 for its core 11 will be reduced. Said core will drop away slightly therefrom, thus pern'iitting the lever 10 to fall. Said lever carrying with it the pawl 9, engaging with the teeth on the plate 8, which carries the brush 7, will move said brush over the contacts ot' the rheostat, thereby cutting out a certain amount of resistance, when the strength of current passing through the solenoid 12 will again be normal and the core will again be attracted, thus drawing up the lever 10, carrying with it the pawl 9. Should the strength of the current again be diminished, this'operation is repeated, and a current of steady strength is thereby maintained. In closing one end of the cylinder 23 the same is flanged, as shown in Figs. 3 and 6, by any of the well-known means new used, and a suitable disk 22 is provided. A support 23, which rests on insulated spring-pressed pins 24, supports said cylinder, and a metallic block 25 rests on the top of the disk, which has been placed on top of said cylinder overlapping its flange. The two terminals 4 15 are connected to the support 23 and block 25, respectively, and the current when applied will heat the joint to a suitable temperature, when the block 21 is moved downwardly and the metal at the joint forced together, thus forming a weld such as shown in Fig. 8. In case of this cylinder being tapered, or, in other words, smaller at its mouth than at the point where the weld is to be made, a collapsible support should be provided for such cylinder, and said support may be of any suitable construction. In securing the outlet 24' for said cylinder in position the said outlet, which may be of a form such as shown in Fig. 9, is formed either by being welded or drawn, and a suitable flange formed thereon is held against the side of said cylinder by a metallic thimble 26, said cylinder being supported on a block 27, which rests on the spring-pressed insulating-pins 28 28, mounted in the support 29 of the press. The electrical terminals of the source of power connect with the support 27 and thimble 2t), and the block 30 is actuated as in forming the previous welds.

WVhile we have herein described this process as applied to cylindrical bodies, yet it will be obvious that the same may be applied to the welding of sheet metal of any form without departing from the general spirit of this invention.

Having fully described our invention, what we claim as new, and desire to secure by Letters Patent, is

The herein-described process for forming vessels from sheet metal consisting in securing the ends of the material to be welded in overlapped position upon an insulating support, mechanically securing a perfect contact between the end portions, connecting said portions adjacent the joint with the terminals of an electrical supply-circuit having a variable re sistance therein and retaining the current at a fixed strength by automatically reducing the 

